1. Field of the invention
The present invention relates to an electrical connector, and more particularly to a ZIF (Zero Insertion Force) socket connector for connecting a central processing unit (CPU) of a computer system to a printed circuit board (PCB).
2. Description of Related Art
ZIF sockets are known in the art for connecting Integrated Circuit (IC) packages to printed circuit boards. U.S. Pat. Nos. 6,338,640, 6,431,900, 6,579,112, 6,254,415 disclose some ZIF socket connectors. Referring to FIG. 6, one example of such conventional connectors comprises a base 2, a cover 3, and an actuator 41. The cover 3 is movably mounted on an upper surface of the base 2. The actuator 41 is in form of a cam comprising at least two cylindrical portions, central axes of which are offset from each other. One of the cylindrical portions interferes with the base 2 and another interferes with the cover 3. When the actuator 41 is rotated, the cam axe moves to push or pull the cover 3 to slide with respect to the base 2, along an anticipative front-to-back direction, that is between a contact insert position and a contact engagement position. When the actuator 41 is rotated to drive the cover 3 to slide along the front-to-back direction, an inevitable force along a left-to-right direction may exert on the cover 3, which causes a sideways movement of the cover 3 with respect to the base 2. When this happens, the cover 3 may slide improperly or even fail to slide.
To overcome above-motioned problems, an improved socket connector is desired.